Capital One Cup heroes Bradford were thrown out of the FA Cup and then quickly reinstated after fielding an ineligible player in their second-round match against Brentford, but they are not the first to have fallen foul of the rules. Here, ESPN picks out a selection of memorable blunders.
Rangers nearly pay the penalty (1971)
In 1972, Rangers lifted the Cup Winners' Cup - the only European trophy in the club's history - but only after manager Willie Waddell highlighted a considerable refereeing blunder to UEFA.
Rangers had won the first leg of their second-round tie with Portuguese side Sporting 3-2 but succumbed to a 4-3 defeat in Lisbon, leaving the scores tied at 6-6. Referee Laurens van Ravens, failing to realise that Rangers had won the tie on away goals, ordered a penalty shootout, which Sporting won.
"It was unbelievable," Rangers winger Willie Henderson told the Daily Record in 2008. "We were sitting in the dressing room with our heads in our hands. There was something in my head about away goals but it seemed we were out."
A member of the Scottish press knocked on the dressing-room door, held a conversation with Waddell, and the newly enlightened Gers boss headed off to find a UEFA official so that he could highlight the appropriate section in the rule book.
Van Ravens recalled: "After the penalties I returned to the dressing room. There, the UEFA officials showed up and told me the good news and the bad news. The good news was that I had controlled an excellent game well. The bad news - Rangers should have won the match." Rangers were awarded the victory and went on to lift the trophy.
Stuttgart's foreign invasion (1992)
Having lost the first leg of their Champions League first-round clash 3-0 at Stuttgart, Leeds United responded magnificently in the return game at Elland Road, winning 4-1. They had lost the tie on away goals, and afterwards a gracious Stuttgart coach Christoph Daum said: "We were the luckier team, not the better."
Yet, less than 24 hours after the match, it was noticed that Daum had played four foreigners, exceeding the three permitted, with the decision to bring on substitutes Adrian Knup and Jovo Simanic in the final ten minutes proving costly. Stuttgart president Gerhard Mayer-Vorfelder pleaded for mercy but added: "If a mistake like that happened in any other organisation, the board would have to be fired straight away."
UEFA ordered a replay on neutral ground, and agreed a lucrative TV rights deal with German company RTL Plus - much to the chagrin of Leeds chairman Leslie Silver, who mischievously said he believed "certain influences affected their judgement". Leeds triumphed 2-1 in Barcelona to progress to the second round, where they were beaten 4-2 by Rangers.
Madrid lose national pride (1994)
Real Madrid turned to Jorge Valdano to spark a revival after a disappointing 1993-94 campaign, but their hopes of winning a first league title since 1990 looked to have been dented on October 23. That day, Madrid had been forced to settle for a 1-1 draw against relegation candidates Compostela and - worse - Valdano had breached the rules in the process.
At that stage, clubs could not field more than three foreign players at any one time in Spain; having started the Compostela game with Fernando Redondo, Michael Laudrup and Ivan Zamorano, Valdano moved to bring on Peter Dubovsky for Luis Enrique in the 83rd minute. Realising his error, he immediately moved to sub him off again.
Nonetheless, the potential penalties were strict, with lengthy suspensions, heavy fines and replays on neutral ground all permitted; in the end, the RFEF's Competition Committee banned Valdano for a month and fined him 663,700 pesetas (£3,237), while the club were fined a further 100,000 (£487).
"Madrid are suffering the consequences of a war which we are not controlling," Valdano said. "I recognised the error, not with the intention of excusing myself, but out of dignity. As a Madridista, I begin to feel worried because a lot of strange things are happening, and this has only begun. In the street, I have heard all kinds of comments and this has begun to take on a dangerous dimension. It could get out of control."
Despite his concerns, Madrid went on to secure the title.
Amateur dramatics at Bayern (1995)
In mid-April 1995, with Bayern sixth in the Bundesliga but still alive in the title race, they faced a potentially tricky trip to Eintracht Frankfurt. The fixture was rendered even more difficult because Bayern were suffering extensive injury problems, and coach Giovanni Trapattoni was able to field only nine professional players. In addition, he picked goalkeeper Sven Scheuer and defender Sammy Kuffour, who were at that stage amateurs (a system explained in Uli Hesse's article here). After 25 minutes, with the score at 1-1, Bayern's injury problems worsened: Thomas Helmer limped off and had to be replaced by another amateur, Marco Grimm, who was making his Bundesliga debut.
Under the rules of the time, Bayern had used their full allocation of amateur players on the field but, in the 72nd minute, with Bayern leading 3-2, Trapattoni decided to make a defensive substitution to preserve the lead: Didi Hamann, another amateur, was readied to replace Marcel Witeczek.
Bayern's press director had spotted the mistake and rushed to the dugout to alert the coach, but he was too late. Eintracht general manager Bernd Holzenbein also realised the error. Bayern eventually won the game 5-2, but as the players filed off the field they were called into the dressing room and made aware of the problem. Eintracht were awarded a 2-0 win, and Trapattoni held his hands up, while Uli Hoeness added: "It is also my fault and [assistant coach] Klaus Augenthaler's. It's embarrassing."
Bayern, who could have submitted an application to field extra amateur players before the game, ultimately finished sixth that year and qualified for the UEFA Cup only because Borussia Monchengladbach, who finished one place ahead by virtue of goal difference, secured a place in the Cup Winners' Cup. In the 1995-96 season, the reprieved Bayern lifted the UEFA Cup.
Oops, Valdano did it again (1997)
Incredibly, Jorge Valdano failed to learn any lessons from the 1994 embarrassment he had described as "possibly the lapse of my life". During his time in charge of Valencia, with rules having changed to permit four non-EU players, he fielded five.
Los Che had endured a poor start to the season but, in the game against Racing Santander on September 14, were leading 1-0. With Ariel Ortega, Claudio Lopez, Goran Vlaovic and Miroslav Djukic already on the field, though, Valdano opted to bring Marcelinho Carioca on from the bench for the final half-hour. The coach quickly realised his error and withdrew Djukic, but with no substitutes remaining had to play the remainder of the game with only ten men. During that time, Valencia conceded two goals and lost the game 2-1.
"No look was comparable yesterday to the sadness that emanated from the eyes of Jorge Valdano," El Pais reported the following day. "He was an image of desolation and failure."
Valencia dismissed Valdano as coach that week.
Hammer blow (2000)
West Ham United believed they had booked their place in the semi-finals of the League Cup in 2000 after beating Aston Villa in a penalty shoot-out following a 2-2 draw. However, Manny Omoyinmi, introduced as a 113th-minute substitute, had already appeared in the competition during a loan spell with Gillingham, and no one at West Ham had noticed that he was cup-tied.
Manager Harry Redknapp blamed a "cock-up", and company secretary Graham Mackrell was obliged to resign in the aftermath. "We acted upon information which was given to me that the player was eligible to play," Mackrell said. "It patently wasn't correct and as a result I'm responsible."
The Football League ordered that the game be replayed, and Villa won 3-1 at Upton Park to book their place in the semi-finals.
Maccabi Haifa fail to get their fax straight (2001)
Maccabi Haifa appeared to have secured a lucrative tie against Liverpool in the third qualifying round of the 2001-02 Champions League after beating Finnish side Haka 5-0 on aggregate. However, in the second leg - a 4-0 win in Israel - Haifa had mistakenly fielded Walid Badir.
The former Wimbledon midfielder had missed the second leg of a UEFA Cup tie with Vitesse Arnhem the previous season through suspension, and the European governing body faxed the club to say that Badir was banned "for two more games"; Haifa misunderstood, believing the suspension amounted to two games in total. UEFA showed no sympathy, arguing that Haifa "displayed culpable negligence by not clarifying the suspension", and handed them a 3-0 defeat.
"There's no one more frustrated than me," Haifa boss Avram Grant said. "My life's ambition was to visit Liverpool as a coach." Haka eventually bowed out of the competition with a 9-1 aggregate defeat to the Reds.
Ruud awakening for Azzurri (2008)
Italy were left furious in their opening match of Euro 2008 as Ruud van Nistelrooy, appearing to be some distance offside, prodded home the first goal of Netherlands' 3-0 victory. The Azzurri players protested and, when the goal was replayed at the Stade de Suisse, there was a furious reaction on and off the field.
FIGC vice-president Demetrio Albertini said after the game: "I think the players had been particularly upset because of the replay on giant screens during the game. It raised the tension and affected both the players and the referee. Also, Luca Toni was booked [for pointing at the screen] and that could have an influence in the games to come." Even the Dutch players were surprised, with Dirk Kuyt telling ITV: "We were waiting for the flag but it didn't come."
However, the officials had got it right. Italy defender Christian Panucci, having clashed with goalkeeper Gianluigi Buffon in the build-up, had been lying behind the goal-line and was - according to Law 11 - therefore playing the striker onside.
UEFA general secretary David Taylor confirmed at a press conference: "The goal was correctly awarded. Not many people, even in the game - and I include the players - know this interpretation."
Zenit and the art of squad maintenance (2011)
In a huge game at the start of the Russian season, Zenit St Petersburg hosted CSKA Moscow. Luciano Spalletti, the Zenit coach, had been so determined to secure a positive result that he decided to ignore a rule stipulating that one homegrown player aged under 21 must be included in the squad.
Zenit drew the match 1-1, and Spalletti explained afterwards: "It wasn't only a match but a match against a top opponent. I needed reliable players on the bench." He had said he was happy to pay the fine for his transgression, as he had done the previous year.
However, as of 2011-12, the authorities had tweaked the rules: neglecting to name a local U-21 player would result in the club responsible forfeiting the match. Zenit were hit with a 3-0 defeat and a 200,000 rouble (£4,500) fine.
Zenit general manager Maxim Mitrofanov blamed several people - including himself - and apologised for the "lack of professionalism and competency of our staff".
Forlan idol at Inter (2011)
When Samuel Eto'o departed Inter Milan for Anzhi Makhachkala, the club invested a reported €5 million on Diego Forlan to fill the void. During the negotiations with Atletico Madrid, Forlan had spoken with his club to ensure he was excluded from the Europa League play-off with Vitoria Guimaraes and would therefore be eligible for Inter's Champions League campaign.
Inter duly included him in their 25-man squad, at the expense of Luc Castaignos, only to learn that Forlan had in fact appeared in the third round of Europa League qualification and would not be eligible for the Champions League until the knockout stages. The striker said he "had no idea that was the case", adding in an Onda Cera interview: "The truth is I didn't know UEFA's rules and so I was going on what I'd been told, which was that it was enough to not play against Vitoria Guimaraes."
Inter thus went into the tournament one man short, and Inter president Massimo Moratti was less than pleased. "I'm sorry mostly for Castaignos because otherwise he could have played," he said. "The Forlan oversight is fairly serious and it's not something we can fix. We have to find a way of avoiding it in the future." Forlan's disappointing stint at the San Siro came to an end after only one season.
South Africa fail to spot the difference (2011)
When South Africa drew 0-0 with Sierra Leone in their final qualification game for the 2012 African Nations Cup, they believed they had reached the finals by virtue of having a superior goal difference to both Niger and Sierra Leone. However, the rules stipulated that Niger, with the best head-to-head record among the three teams tied on points, would advance.
At the end of their game, the South Africa players had danced, hugged coach Pitso Mosimane and embarked on a lap of honour, while South African Football Association president Kirsten Nematandani appeared on television to praise the team's achievement.
Once made aware of their error, South Africa embarked on a desperate campaign to make amends, with SAFA CEO Robin Petersen expressing a view that "this particular rule should be thrown out because it defeats the traditional way of determining a standing". Mosimane, who said he had been unaware of the tournament rules, argued that the European and South American reliance on goal difference was "much better" and added: "Africa is a jungle, my friend." SAFA president Nematandani was the most forthright, declaring on the eNews TV channel: "Those rules are wrong."
However, the country's sports minister, Fikile Mbalula, reserved his indignation for SAFA, demanding the body apologise to the country, and added: "The best thing is to accept the defeat and mediocrity on the part of the leadership and move on."
It emerged that Mosimaneto had adopted defensive tactics in the match on the prompting of a commentator, who had mistakenly informed the team's support staff that a draw would have been sufficient, and a repentant Nematandani said: "The failure by members of our technical team to acquaint themselves with some of the CAF rules is unacceptable and we will look into our internal structures."